This pull request reuses the typed_keys parameter added in #22965, but this time it applies it to suggesters. When set to true, the suggester names in the search response will be prefixed with a prefix that reflects their type.
This pull request adds a new parameter to the REST Search API named `typed_keys`. When set to true, the aggregation names in the search response will be prefixed with a prefix that reflects the internal type of the aggregation.
Here is a simple example:
```
GET /_search?typed_keys
{
"aggs": {
"tweets_per_user": {
"terms": {
"field": "user"
}
}
},
"size": 0
}
```
And the response:
```
{
"aggs": {
"sterms:tweets_per_user": {
...
}
}
}
```
This parameter is intended to make life easier for REST clients that could parse back the prefix and could detect the type of the aggregation to parse. It could also be implemented for suggesters.
We have a bunch of interfaces that have only a single implementation
for 6 years now. These interfaces are pretty useless from a SW development
perspective and only add unnecessary abstractions. They also require
lots of casting in many places where we expect that there is only one
concrete implementation. This change removes the interfaces, makes
all of the classes final and removes the duplicate `foo` `getFoo` accessors
in favor of `getFoo` from these classes.
This commit adds support for the newline delimited JSON Content-Type, which is how
the bulk, multi-search, and multi-search template APIs expect data to be formatted. The
`elasticsearch-js` client has also been using this content type for these types of requests.
Closes#22943
This commit upgrades the checkstyle configuration from version 5.9 to
version 7.5, the latest version as of today. The main enhancement
obtained via this upgrade is better detection of redundant modifiers.
Relates #22960
This change adds a strict mode for xcontent parsing on the rest layer. The strict mode will be off by default for 5.x and in a separate commit will be enabled by default for 6.0. The strict mode, which can be enabled by setting `http.content_type.required: true` in 5.x, will require that all incoming rest requests have a valid and supported content type header before the request is dispatched. In the non-strict mode, the Content-Type header will be inspected and if it is not present or not valid, we will continue with auto detection of content like we have done previously.
The content type header is parsed to the matching XContentType value with the only exception being for plain text requests. This value is then passed on with the content bytes so that we can reduce the number of places where we need to auto-detect the content type.
As part of this, many transport requests and builders were updated to provide methods that
accepted the XContentType along with the bytes and the methods that would rely on auto-detection have been deprecated.
In the non-strict mode, deprecation warnings are issued whenever a request with body doesn't provide the Content-Type header.
See #19388
Currently, stored scripts use a namespace of (lang, id) to be put, get, deleted, and executed. This is not necessary since the lang is stored with the stored script. A user should only have to specify an id to use a stored script. This change makes that possible while keeping backwards compatibility with the previous namespace of (lang, id). Anywhere the previous namespace is used will log deprecation warnings.
The new behavior is the following:
When a user specifies a stored script, that script will be stored under both the new namespace and old namespace.
Take for example script 'A' with lang 'L0' and data 'D0'. If we add script 'A' to the empty set, the scripts map will be ["A" -- D0, "A#L0" -- D0]. If a script 'A' with lang 'L1' and data 'D1' is then added, the scripts map will be ["A" -- D1, "A#L1" -- D1, "A#L0" -- D0].
When a user deletes a stored script, that script will be deleted from both the new namespace (if it exists) and the old namespace.
Take for example a scripts map with {"A" -- D1, "A#L1" -- D1, "A#L0" -- D0}. If a script is removed specified by an id 'A' and lang null then the scripts map will be {"A#L0" -- D0}. To remove the final script, the deprecated namespace must be used, so an id 'A' and lang 'L0' would need to be specified.
When a user gets/executes a stored script, if the new namespace is used then the script will be retrieved/executed using only 'id', and if the old namespace is used then the script will be retrieved/executed using 'id' and 'lang'
This commit adds a SpecialPermission constant and uses that constant
opposed to introducing new instances everywhere.
Additionally, this commit introduces a single static method to check that
the current code has permission. This avoids all the duplicated access
blocks that exist currently.
There are presently 7 ctor args used in any rest handlers:
* `Settings`: Every handler uses it to initialize a logger and
some other strange things.
* `RestController`: Every handler registers itself with it.
* `ClusterSettings`: Used by `RestClusterGetSettingsAction` to
render the default values for cluster settings.
* `IndexScopedSettings`: Used by `RestGetSettingsAction` to get
the default values for index settings.
* `SettingsFilter`: Used by a few handlers to filter returned
settings so we don't expose stuff like passwords.
* `IndexNameExpressionResolver`: Used by `_cat/indices` to
filter the list of indices.
* `Supplier<DiscoveryNodes>`: Used to fill enrich the response
by handlers that list tasks.
We probably want to reduce these arguments over time but
switching construction away from guice gives us tighter
control over the list of available arguments.
These parameters are passed to plugins using
`ActionPlugin#initRestHandlers` which is expected to build and
return that handlers immediately. This felt simpler than
returning an reference to the ctors given all the different
possible args.
Breaks java plugins by moving rest handlers off of guice.
This commit tries to simplify the way ElasticsearchException are rendered to xcontent. It adds some documentation and renames and merges some methods. Current behavior is preserved, the goal is to be more readable and centralize everything in the ElasticsearchException class.
Removes `AggregatorParsers`, replacing all of its functionality with
`XContentParser#namedObject`.
This is the third bit of payoff from #22003, one less thing to pass
around the entire application.
* Remove a checked exception, replacing it with `ParsingException`.
* Remove all Parser classes for the yaml sections, replacing them with static methods.
* Remove `ClientYamlTestFragmentParser`. Isn't used any more.
* Remove `ClientYamlTestSuiteParseContext`, replacing it with some static utility methods.
I did not rewrite the parsers using `ObjectParser` because I don't think it is worth it right now.
Introduces `XContentParser#namedObject which works a little like
`StreamInput#readNamedWriteable`: on startup components register
parsers under names and a superclass. At runtime we look up the
parser and call it to parse the object.
Right now the parsers take a context object they use to help with
the parsing but I hope to be able to eliminate the need for this
context as most what it is used for at this point is to move
around parser registries which should be replaced by this method
eventually. I make no effort to do so in this PR because it is
big enough already. This is meant to the a start down a road that
allows us to remove classes like `QueryParseContext`,
`AggregatorParsers`, `IndicesQueriesRegistry`, and
`ParseFieldRegistry`.
The goal here is to reduce the amount of plumbing required to
allow parsing pluggable things. With this you don't have to pass
registries all over the place. Instead you must pass a super
registry to fewer places and use it to wrap the reader. This is
the same tradeoff that we use for NamedWriteable and it allows
much, much simpler binary serialization. We think we want that
same thing for xcontent serialization.
The only parsing actually converted to this method is parsing
`ScoreFunctions` inside of `FunctionScoreQuery`. I chose this
because it is relatively self contained.
We are currenlty checking that no deprecation warnings are emitted in our query tests. That can be moved to ESTestCase (disabled in ESIntegTestCase) as it allows us to easily catch where our tests use deprecated features and assert on the expected warnings.
We return deprecation warnings as response headers, besides logging them. Strict parsing mode stayed around, but was only used in query tests, though we also introduced checks for deprecation warnings there that don't need strict parsing anymore (see #20993).
We can then safely remove support for strict parsing mode. The final goal is to remove the ParseFieldMatcher class, but there are many many users of it. This commit prepares the field for the removal, by deprecating ParseFieldMatcher and making it effectively not needed. Strict parsing is removed from ParseFieldMatcher, and strict parsing is replaced in tests where needed with deprecation warnings checks.
Note that the setting to enable strict parsing was never ported to the new settings infra hance it cannot be set in production. It is really only used in our own tests.
Relates to #19552
Our query DSL supports empty queries (`{}`), which have a different meaning depending on the query that holds it, either ignored, match_all or match_none. We deprecated the support for empty queries in 5.0, where we log a deprecation warning wherever they are used.
The way we supported it once we moved query parsing to the coordinating node was having an Optional<QueryBuilder> return type in all of our parse methods (called fromXContent). See #17624. The central place for this was QueryParseContext#parseInnerQueryBuilder. We can now remove all the optional return types and simply throw an exception whenever an empty query is found.
To get #22003 in cleanly we need to centralize as much `XContentParser` creation as possible into `RestRequest`. That'll mean we have to plumb the `NamedXContentRegistry` into fewer places.
This removes `RestAction.hasBody`, `RestAction.guessBodyContentType`, and `RestActions.getRestContent`, moving callers over to `RestRequest.hasContentOrSourceParam`, `RestRequest.contentOrSourceParam`, and `RestRequest.contentOrSourceParamParser` and `RestRequest.withContentOrSourceParamParserOrNull`. The idea is to use `withContentOrSourceParamParserOrNull` if you need to handle requests without any sort of body content and to use `contentOrSourceParamParser` otherwise.
I believe the vast majority of this PR to be purely mechanical but I know I've made the following behavioral change (I'll add more if I think of more):
* If you make a request to an endpoint that requires a request body and has cut over to the new APIs instead of getting `Failed to derive xcontent` you'll get `Body required`.
* Template parsing is now non-strict by default. This is important because we need to be able to deprecate things without requests failing.
SearchTemplateRequest to implement CompositeIndicesRequest
Given that SearchTemplateRequest effectively delegates to search when a search is being executed, it should implement the CompositeIndicesRequest interface. The subrequests method should return a single search request. When a search is not going to be executed, because we are in simulate mode, there are no inner requests, and there are no corresponding indices to that request either.
Closes#21747
At one point in the past when moving out the rest tests from core to
their own subproject, we had multiple test classes which evenly split up
the tests to run. However, we simplified this and went back to a single
test runner to have better reproduceability in tests. This change
removes the remnants of that multiplexing support.
This adds checks for expected warning headers to the query builder test
infrastructure. Tests that are adding deprecation warnings to the response
headers need to check those, otherwise the abstract base class for the test
class will complain at teardown.
Refactored ScriptType to clean up some of the variable and method names. Added more documentation. Deprecated the 'in' ParseField in favor of 'stored' to match the indexed scripts being replaced by stored scripts.
Today SearchContext expose the current context as a thread local which makes any kind of sane interface design very very hard. This PR removes the thread local entirely and instead passes the relevant context anywhere needed. This simplifies state management dramatically and will allow for a much leaner SearchContext interface down the road.
Today when parsing a request, Elasticsearch silently ignores incorrect
(including parameters with typos) or unused parameters. This is bad as
it leads to requests having unintended behavior (e.g., if a user hits
the _analyze API and misspell the "tokenizer" then Elasticsearch will
just use the standard analyzer, completely against intentions).
This commit removes lenient URL parameter parsing. The strategy is
simple: when a request is handled and a parameter is touched, we mark it
as such. Before the request is actually executed, we check to ensure
that all parameters have been consumed. If there are remaining
parameters yet to be consumed, we fail the request with a list of the
unconsumed parameters. An exception has to be made for parameters that
format the response (as opposed to controlling the request); for this
case, handlers are able to provide a list of parameters that should be
excluded from tripping the unconsumed parameters check because those
parameters will be used in formatting the response.
Additionally, some inconsistencies between the parameters in the code
and in the docs are corrected.
Relates #20722
We can now run templates using `explain` and/or `profile` parameters.
Which is interesting when you have defined a complicated profile but want to debug it in an easier way than running the full query again.
You can use `explain` parameter when running a template:
```js
GET /_search/template
{
"file": "my_template",
"params": {
"status": [ "pending", "published" ]
},
"explain": true
}
```
You can use `profile` parameter when running a template:
```js
GET /_search/template
{
"file": "my_template",
"params": {
"status": [ "pending", "published" ]
},
"profile": true
}
```
This commit modifies the call sites that allocate a parameterized
message to use a supplier so that allocations are avoided unless the log
level is fine enough to emit the corresponding log message.
Parsing a search request is currently split up among a number of
classes, using multiple public static methods, which take multiple
regstries of elements that may appear in the search request like query
parsers and aggregations. This change begins consolidating all this code
by collapsing the registries normally used for parsing search requests
into a single SearchRequestParsers class. It is also made available to
plugin services to enable templating of search requests. Eventually all
of the actual parsing logic should move to the class, and the registries
should be hidden, but for now they are at least co-located to reduce the
number of objects that must be passed around.
Squashes all the subpackages of `org.elasticsearch.rest.action` down to
the following:
* `o.e.rest.action.admin` - Administrative actions
* `o.e.rest.action.cat` - Actions that make tables for `grep`ing
* `o.e.rest.action.document` - Actions that act on documents
* `o.e.rest.action.ingest` - Actions that act on ingest pipelines
* `o.e.rest.action.search` - Actions that search
I'm tempted to merge `search` into `document` but the `document`
package feels fairly complete as is and `Suggest` isn't actually always
about documents either....
I'm also tempted to merge `ingest` into `admin.cluster` because the
latter contains the actions for dealing with stored scripts.
I've moved the `o.e.rest.action.support` into `o.e.rest.action`.
I've also added `package-info.java`s to all packges in `o.e.rest`. I
figure if the package is too small to deserve a `package-info.java` file
then it is too small to deserve to be a package....
Also fixes checkstyle in all moved classes.
When compiling many dynamically changing scripts, parameterized
scripts (<https://www.elastic.co/guide/en/elasticsearch/reference/master/modules-scripting-using.html#prefer-params>)
should be preferred. This enforces a limit to the number of scripts that
can be compiled within a minute. A new dynamic setting is added -
`script.max_compilations_per_minute`, which defaults to 15.
If more dynamic scripts are sent, a user will get the following
exception:
```json
{
"error" : {
"root_cause" : [
{
"type" : "circuit_breaking_exception",
"reason" : "[script] Too many dynamic script compilations within one minute, max: [15/min]; please use on-disk, indexed, or scripts with parameters instead",
"bytes_wanted" : 0,
"bytes_limit" : 0
}
],
"type" : "search_phase_execution_exception",
"reason" : "all shards failed",
"phase" : "query",
"grouped" : true,
"failed_shards" : [
{
"shard" : 0,
"index" : "i",
"node" : "a5V1eXcZRYiIk8lecjZ4Jw",
"reason" : {
"type" : "general_script_exception",
"reason" : "Failed to compile inline script [\"aaaaaaaaaaaaaaaa\"] using lang [painless]",
"caused_by" : {
"type" : "circuit_breaking_exception",
"reason" : "[script] Too many dynamic script compilations within one minute, max: [15/min]; please use on-disk, indexed, or scripts with parameters instead",
"bytes_wanted" : 0,
"bytes_limit" : 0
}
}
}
],
"caused_by" : {
"type" : "general_script_exception",
"reason" : "Failed to compile inline script [\"aaaaaaaaaaaaaaaa\"] using lang [painless]",
"caused_by" : {
"type" : "circuit_breaking_exception",
"reason" : "[script] Too many dynamic script compilations within one minute, max: [15/min]; please use on-disk, indexed, or scripts with parameters instead",
"bytes_wanted" : 0,
"bytes_limit" : 0
}
}
},
"status" : 500
}
```
This also fixes a bug in `ScriptService` where requests being executed
concurrently on a single node could cause a script to be compiled
multiple times (many in the case of a powerful node with many shards)
due to no synchronization between checking the cache and compiling the
script. There is now synchronization so that a script being compiled
will only be compiled once regardless of the number of concurrent
searches on a node.
Relates to #19396
This commit updates Jackson to the 2.8.1 version, which is more strict when it comes to build objects. It also adds the snakeyaml dependency that was previously shaded in jackson libs.
It also closes#18076
Adds `warnings` syntax to the yaml test that allows you to expect
a `Warning` header that looks like:
```
- do:
warnings:
- '[index] is deprecated'
- quotes are not required because yaml
- but this argument is always a list, never a single string
- no matter how many warnings you expect
get:
index: test
type: test
id: 1
```
These are accessible from the docs with:
```
// TEST[warning:some warning]
```
This should help to force you to update the docs if you deprecate
something. You *must* add the warnings marker to the docs or the build
will fail. While you are there you *should* update the docs to add
deprecation warnings visible in the rendered results.
After #13834 many tests that used Groovy scripts (for good or bad reason) in their tests have been moved in the lang-groovy module and the issue #13837 has been created to track these messy tests in order to clean them up.
The work started with #19280, #19302 and #19336 and this PR moves the remaining messy tests back in core, removes the dependency on Groovy, changes the scripts in order to use the mocked script engine, and change the tests to integration tests.
It also moves IndexLookupIT test back (even if it has good chance to be removed soon) and fixes its tests.
It also changes AbstractQueryTestCase to use custom script plugins in tests.
closes#13837
In an effort to reduce the number of tiny packages we have in the
code base this moves all the files that were in subdirectories of
`org.elasticsearch.rest.action.admin.cluster` into
`org.elasticsearch.rest.action.admin.cluster`.
Also fixes line length in these packages.
This makes it obvious that these tests are for running the client yaml
suites. Now that there are other ways of running tests using the REST
client against a running cluster we can't go on calling the shared
client yaml tests "REST tests". They are rest tests, but they aren't
**the** rest tests.
This adds a header that looks like `Location: /test/test/1` to the
response for the index/create/update API. The requirement for the header
comes from https://www.w3.org/Protocols/rfc2616/rfc2616-sec10.htmlhttps://tools.ietf.org/html/rfc7231#section-7.1.2 claims that relative
URIs are OK. So we use an absolute path which should resolve to the
appropriate location.
Closes#19079
This makes large changes to our rest test infrastructure, allowing us
to write junit tests that test a running cluster via the rest client.
It does this by splitting ESRestTestCase into two classes:
* ESRestTestCase is the superclass of all tests that use the rest client
to interact with a running cluster.
* ESClientYamlSuiteTestCase is the superclass of all tests that use the
rest client to run the yaml tests. These tests are shared across all
official clients, thus the `ClientYamlSuite` part of the name.
Messy tests with mustache were either moved to core, moved to a rest test or remained untouched if they actually tested mustache.
Also removed tests that were redundant.
Remove `ParseField` constants used for names where there are no deprecated
names and just use the `String` version of the registration method instead.
This is step 2 in cleaning up the plugin interface for extending
search time actions. Aggregations are next.
This is breaking for plugins because those that register a new query should
now implement `SearchPlugin` rather than `onModule(SearchModule)`.
* Removed `Template` class and unified script & template parsing logic. Templates are scripts, so they should be defined as a script. Unless there will be separate template infrastructure, templates should share as much code as possible with scripts.
* Removed ScriptParseException in favour for ElasticsearchParseException
* Moved TemplateQueryBuilder to lang-mustache module because this query is hard coded to work with mustache only
Switches most search behavior extensions from push (`onModule(SearchModule)`)
to pull (`implements SearchPlugin`). This effort in general gives plugin
authors a much cleaner view of how to extend Elasticsearch and starts to
set up portions of Elasticsearch as "the plugin API". This commit in
particular does that for search-time behavior like customized suggesters,
highlighters, score functions, and significance heuristics.
It also switches most such customization to being done at search module
construction time which is much, much easier to reason about from a testing
perspective. It also helps significantly in the process of de-guice-ing
Elasticsearch's startup.
There are at least two major search time extensions that aren't covered in
this commit that will simply have to wait for the next commit on the topic
because this one has already grown large: custom aggregations and custom
queries. These will likely live in the same SearchPlugin interface as well.
This commit renames writeThrowable to writeException. The situation here
stems from the fact that the StreamOutput method for serializing
Exceptions needs to accept Throwables too as Throwables can be the cause
of serialized Exceptions. Yet, we do not serialize Throwables in the
Error sub-hierarchy in a way that they can be deserialized into their
initial type. This leads to an asymmetry in the StreamOutput method for
serializing Exceptions and the StreamInput method for writing
Excpetions. Namely, the former will accept Throwables but the latter
will only return Exceptions. A goal with the stream methods has always
been symmetry in the method names so that serialization/deserialization
routines appear symmetrical in code. It is this asymmetry on the
input/output types for Exceptions on StreamOutput/StreamInput that
clashes with the desired symmetry of naming. Despite this, we should
favor symmetry in the naming of the methods. This commit renames
StreamOutput#writeThrowable to StreamOutput#writeException which leaves
us with Exception StreamInput#readException and void
StreamOutput#writeException(Throwable).
Today throughout the codebase, catch throwable is used with reckless
abandon. This is dangerous because the throwable could be a fatal
virtual machine error resulting from an internal error in the JVM, or an
out of memory error or a stack overflow error that leaves the virtual
machine in an unstable and unpredictable state. This commit removes
catch throwable from the codebase and removes the temptation to use it
by modifying listener APIs to receive instances of Exception instead of
the top-level Throwable.
Relates #19231
BytesReference should be a really simple interface, yet it has a gazillion
ways to achieve the same this. Methods like `#hasArray`, `#toBytesArray`, `#copyBytesArray`
`#toBytesRef` `#bytes` are all really duplicates. This change simplifies the interface
dramatically and makes implementations of it much simpler. All array access has been removed
and is streamlined through a single `#toBytesRef` method. Utility methods to materialize a
compact byte array has been added too for convenience.
We'll migrate to NamedWriteable so we can share code with the rest
of the system. So we can work on this in multiple pull requests without
breaking Elasticsearch in between the commits this change supports
*both* old style `InternalAggregations.stream` serialization and
`NamedWriteable` style serialization. As such it creates about a
half dozen `// NORELEASE` comments that will have to be removed
once the migration is complete.
This also introduces a boolean `transportClient` flag to `SearchModule`
which is used to skip inappropriate registrations for for the
transport client while still registering the things it needs. In
this case that means that the `InternalAggregation` subclasses are
registered with the `NamedWriteableRegistry` but the `AggregationBuilder`
subclasses are not.
Finally, this moves aggregation registration from guice configuration
time to `SearchModule` construction time. This will make it simpler to
work with in the future as we further clean up Elasticsearch's
extension points.
Previously all rest handlers would take Client in their injected ctor.
However, it was only to hold the client around for runtime. Instead,
this can be done just once in the HttpService which handles rest
requests, and passed along through the handleRequest method. It also
should always be a NodeClient, and other types of Clients (eg a
TransportClient) would not work anyways (and some handlers can be
simplified in follow ups like reindex by taking NodeClient).
`RestHandler`s are highly tied to actions so registering them in the
same place makes sense.
Removes the need to for plugins to check if they are in transport client
mode before registering a RestHandler - `getRestHandlers` isn't called
at all in transport client mode.
This caused guice to throw a massive fit about the circular dependency
between NodeClient and the allocation deciders. I broke the circular
dependency by registering the actions map with the node client after
instantiation.
This pull request adds two util functions to the Mustache templating engine:
- {{#toJson}}my_map{{/toJson}} to render a Map parameter as a JSON string
- {{#join}}my_iterable{{/join}} to render any iterable (including arrays) as a comma separated list of values like `1, 2, 3`. It's also possible de change the default delimiter (comma) to something else.
closes#18970
Stored scripts are pulled from the cluster state, and the current api
requires passing the ClusterState on each call to compile. However, this
means every user of the ScriptService needs to depend on the
ClusterService. Instead, this change makes the ScriptService a
ClusterStateListener. It also simplifies tests a lot, as they no longer
need to create fake cluster states (except when testing stored scripts).
Instead of implementing onModule(ActionModule) to register actions,
this has plugins implement ActionPlugin to declare actions. This is
yet another step in cleaning up the plugin infrastructure.
While I was in there I switched AutoCreateIndex and DestructiveOperations
to be eagerly constructed which makes them easier to use when
de-guice-ing the code base.
Instead of plugins calling `registerTokenizer` to extend the analyzer
they now instead have to implement `AnalysisPlugin` and override
`getTokenizer`. This lines up extending plugins in with extending
scripts. This allows `AnalysisModule` to construct the `AnalysisRegistry`
immediately as part of its constructor which makes testing anslysis
much simpler.
This also moves the default analysis configuration into `AnalysisModule`
which is how search is setup.
Like `ScriptModule`, `AnalysisModule` no longer extends `AbstractModule`.
Instead it is only responsible for building `AnslysisRegistry`. We still
bind `AnalysisRegistry` but we only do so in `Node`. This is means it
is available at module construction time so we slowly remove the need to
bind it in guice.
This commit moves template support out of the Search API to its own dedicated Search Template API in the lang-mustache module. It provides a new SearchTemplateAction that can be used to render templates before it gets delegated to the usual Search API. The current REST endpoint are identical, but the Render Search Template endpoint now uses the same Search Template API with a new "simulate" option. When this option is enabled, the Search Template API only renders template and returns immediatly, without executing the search.
Closes#17906
This changes adds a MapperPlugin interface which allows pull style
retrieval of mappers and metadata mappers added by plugins. For now, I
have kept the MapperRegistry, but this should be removed in the future
as it is just a silly container for 2 maps which could themselves be
passed around.
Makes ScriptModule just a plain class that manages building the
ScriptSettings and ScriptService from plugins. When we *need*
to bind ScriptService with guice we bind it in a lambda.
Today we have a push model for registering basically anything. All our extension points
are defined on modules which we pass in to plugins. This is harder to maintain and adds
unnecessary dependencies on the modules itself. This change moves towards a pull model
where the plugin offers a getter kind of method to get the extensions. This will also
help in the future if we need to pass dependencies to the extension points which can
easily be defined on the method as arguments if a pull model is used.
Registering a script engine or native scripts still uses Guice today
and is much more complicated than needed. This change moves to a pull
based model where script plugins have to implement a dedicated interface
`ScriptPlugin` and defines simple getter returning instances rather than
classes.
In 2.0 we added plugin descriptors which require defining a name and
description for the plugin. However, we still have name() and
description() which must be overriden from the Plugin class. This still
exists for classpath plugins. But classpath plugins are mainly for
tests, and even then, referring to classpath plugins with their class is
a better idea. This change removes name() and description(), replacing
the name for classpath plugins with the full class name.
This commit refactors the handling of thread pool settings so that the
individual settings can be registered rather than registering the top
level group. With this refactoring, individual plugins must now register
their own settings for custom thread pools that they need, but a
dedicated API is provided for this in the thread pool module. This
commit also renames the prefix on the thread pool settings from
"threadpool" to "thread_pool". This enables a hard break on the settings
so that:
- some of the settings can be given more sensible names (e.g., the max
number of threads in a scaling thread pool is now named "max" instead
of "size")
- change the soft limit on the number of threads in the bulk and
indexing thread pools to a hard limit
- the settings names for custom plugins for thread pools can be
prefixed (e.g., "xpack.watcher.thread_pool.size")
- remove dynamic thread pool settings
Relates #18674
Tanguy Leroux
Simon Willnauer
Jay Modi
Jason Tedor
Jack Conradson
Tim Brooks
Nik Everett
javanna
Daniel Mitterdorfer
Luca Cavanna
Boaz Leskes
Ryan Ernst
Christoph Büscher
Simon Willnauer
David Pilato
Alexander Reelsen
Lee Hinman
Martijn van Groningen
Areek Zillur